org.oryxeditor.server.BPELImporter.java Source code

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Here is the source code for org.oryxeditor.server.BPELImporter.java

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package org.oryxeditor.server;

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.List;
import java.util.logging.Logger;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.w3c.dom.Document;

/**
 * Copyright (c) 2008-2009 
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
public class BPELImporter extends HttpServlet {

    private static final long serialVersionUID = 316274845723034029L;

    private BPELImportPreprocessor preprocessor = new BPELImportPreprocessor();

    private Logger log = Logger.getLogger("org.oryxeditor.server.BPELImporter");

    /**
     * The POST request.
     */
    protected void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException {
        // No isMultipartContent => Error
        final boolean isMultipartContent = ServletFileUpload.isMultipartContent(req);
        if (!isMultipartContent) {
            printError(res, "No Multipart Content transmitted.");
            return;
        }

        // Get the uploaded file
        final FileItemFactory factory = new DiskFileItemFactory();
        final ServletFileUpload servletFileUpload = new ServletFileUpload(factory);
        servletFileUpload.setSizeMax(-1);
        final List<?> items;
        try {
            items = servletFileUpload.parseRequest(req);
            if (items.size() != 1) {
                printError(res, "Not exactly one File.");
                return;
            }
        } catch (FileUploadException e) {
            handleException(res, e);
            return;
        }

        // === prepare the bpel source ===
        // Get filename and content
        final FileItem fileItem = (FileItem) items.get(0);
        final String fileName = fileItem.getName();

        if (!fileName.endsWith(".bpel")) {
            printError(res, "No file with .bepl extension uploaded.");
            return;
        }

        final String fileContent = fileItem.getString();

        // do a pre-processing on this bpel source
        // in this preprocessor the following works will be done:
        //     1. mark all node stencil sets with the attribute "isNodeStencilSet"
        //         mark all edge stencil sets with the attribute "isEdgeStencilSet"
        //         in order to avoid the prefix problem
        //     2. calculate the bounds of each shape
        //      3. generate for each shape a ID
        //     4. move the <link> elements from <links> element to
        //         top of the root <process> element, and record linkID
        //         as the value of element <outgoing> under the corresponding
        //         activity, so they could be easier to handle in BPEL2eRDF.xslt
        //      5. integrate the first <condition> and <activity> element
        //         under a If-block into a <elseIF> element, so they
        //         they could be easier to transform in BPEL2eRDF.xslt
        //      6. transform the value of attribute "opaque" from "yes" to "true"
        final String newContent = preprocessSource(res, fileContent);

        log.fine("newContent:");
        log.fine(newContent);

        // Get the input stream   
        final InputStream inputStream = new ByteArrayInputStream(newContent.getBytes());

        // Get the bpel source
        final Source bpelSource = new StreamSource(inputStream);

        // === prepare the xslt source ===
        // BPEL2eRDF XSLT source
        final String xsltFilename = getServletContext().getRealPath("/xslt/BPEL2eRDF.xslt");
        //       final String xsltFilename = System.getProperty("catalina.home") + "/webapps/oryx/xslt/BPEL2eRDF.xslt";
        final File bpel2eRDFxsltFile = new File(xsltFilename);
        final Source bpel2eRDFxsltSource = new StreamSource(bpel2eRDFxsltFile);

        // Transformer Factory
        final TransformerFactory transformerFactory = TransformerFactory.newInstance();

        // === Get the eRDF result ===
        String resultString = null;
        try {
            Transformer transformer = transformerFactory.newTransformer(bpel2eRDFxsltSource);
            transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
            StringWriter writer = new StringWriter();
            transformer.transform(bpelSource, new StreamResult(writer));
            resultString = writer.toString();
        } catch (Exception e) {
            handleException(res, e);
            return;
        }

        log.fine("reslut-XML");
        log.fine(resultString);

        if (resultString == null) {
            printResponse(res, "transformation error");
        }

        Repository rep = new Repository("");
        resultString = rep.erdfToJson(resultString, getServletContext());

        log.fine("reslut-json");
        log.fine(resultString);

        printResponse(res, resultString);
    }

    private String preprocessSource(HttpServletResponse res, String oldString) {

        StringWriter stringOut = new StringWriter();
        try {
            // transform string to document
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            factory.setNamespaceAware(true);
            DocumentBuilder builder = factory.newDocumentBuilder();
            InputStream oldResultInputStream = new ByteArrayInputStream(oldString.getBytes());
            Document oldDocument = builder.parse(oldResultInputStream);

            // rearrange document
            Document newDocument = preprocessor.preprocessDocument(oldDocument);

            // transform document to string
            TransformerFactory tFactory = TransformerFactory.newInstance();
            Transformer transformer = tFactory.newTransformer();
            DOMSource source = new DOMSource(newDocument);
            StreamResult result = new StreamResult(stringOut);
            transformer.transform(source, result);
            stringOut.flush();

        } catch (Exception e) {
            handleException(res, e);
        }

        return stringOut.toString();

    }

    private void printResponse(HttpServletResponse res, String text) {
        if (res != null) {

            res.setContentType("text/html"); // as required by http://www.extjs.com/deploy/dev/docs/output/Ext.form.BasicForm.html
            res.setStatus(HttpServletResponse.SC_OK);

            // Get the PrintWriter
            PrintWriter out = null;
            try {
                out = res.getWriter();
            } catch (IOException e) {
                e.printStackTrace();
            }

            out.print("{success:true, content:'" + text + "'}");
        }
    }

    private void printError(HttpServletResponse res, String err) {
        if (res != null) {

            // Get the PrintWriter
            res.setContentType("text/html"); // as required by http://www.extjs.com/deploy/dev/docs/output/Ext.form.BasicForm.html
            res.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);

            PrintWriter out = null;
            try {
                out = res.getWriter();
            } catch (IOException e) {
                e.printStackTrace();
            }

            out.print("{success:false, content:'" + err + "'}");
        }
    }

    private void handleException(HttpServletResponse res, Exception e) {
        e.printStackTrace();
        printError(res, e.getLocalizedMessage());
    }

}